In general, lighting industries have a long history together with the history of mankind and are closely related with the mankind.
In recent years, lighting industries are being continuously developed, and various studies with respect to a lighting source, a light emitting method, a driving method, improvement in efficiency, and the like are being variously conducted.
Incandescent lamps, discharge lamps, fluorescent lamps, and the like may be used mainly used as light sources that are mainly used for lighting in recent years. The lighting sources are being used for various purposes such as household lightings, industrial lightings, and the like.
Among these light sources, resistive light sources such as the incandescent lamps may have low efficiency and high heat generation. Also, in case of discharge, there are problems in high price or high voltage. Also, in case of the fluorescent lamps, environmental problems due to the use of mercury may occur.
To solve the disadvantages of the light sources, interests with respect to light emitting diode (LED) lightings having many advantages such as efficiency, diversity in color, freedom in design are being increasing.
Such an LED may be a semiconductor device that emits light when a forward voltage is applied. The LED may have a long lifecycle, low power consumption, and electrical, optical, and physical properties that are adequate for mass production. Thus, the LED may be quickly substituted for the incandescent lamps and fluorescent lamps.
In recent years, many attempts have been made to apply a surface light emitting backlight unit to lighting apparatuses such as stands that are mainly used for televisions.
However, most of lighting apparatuses may be provided as products having only a lighting function, and convergence lighting apparatuses that are grafted to IT technologies may be rare.